Go for it, but don't expect to "finish it." There's so much content at this point you'll never complete it all before the servers close. I mean some things (like Assault) are basically impossible to complete at this point anyway(they require multiple people, and there's no reason to do them so good luck), but on top of that all the questing, slaying, mission work is a good 4-5 years of constant playtime away.

The upside is that the game has changed quite a bit to be more solo-friendly (other than stupid trout like Assault) so you can do a lot of the content without having to have someone join you. I'm just not sure about capped content like some of the CoP fights. It might be possible to solo them somehow now, but more than likely, you'll be stuck begging people to help. Good luck though. If you show up on Shiva, find me.